How do I print on both sides of the paper (duplex)?

For the P1600 series: Automatic duplexing is supported and can be enabled by checking the 'Print on both sides' option in the Finishing tab of the printer driver. For the P1560 series: Manual duplexing is used—print the first side, then retrieve the stack from the output bin, place it printed-side down in the main tray, and press the go button on the control panel to print the second side.